Anticancer antimetabolites

Cladribine [ban, inn] (Leustat Leustatln ) is a synthetic deoxyadenosine derivative and an antimetabolite anticancer AGENT used to treat leukaemia. 

NSC 312887 Fludara ) is a nucleotide antimetabolite ANTICANCER AGENT, used to treat leukaemia (chronic B-cell lymphocytic leukaemia, CLL). 

Describe the general mechanism of action of antimetabolite anticancer agents. 

Antimetabolites. AntimetaboHtes, which represent one of the earliest groups of anticancer agents, are Hsted ia Table 1. Stmctures are showa... 

Anticancer antimetabolites Antimetabolic agents An-tineoplastic antimetabolites... 

Anticancer drugs act on cells in active proliferation and may interfere with a specific phase of the cell cycle or act independently from it. Some of these drugs are naturally occurring compounds, identified in plants or microorganisms, some are synthetic chemicals. Among the major classes of chemotherapeutics include antimetabolites, alkylating agents, inhibitors of the... 

The ability of certain anticancer agents to suppress both humoral and cellular immunity has been exploited in the field of organ transplantation and in diseases thought to be caused by an abnormal or heightened immune response. In particular, the alkylating agents cyclophosphamide and chlorambucil have been used in this context, as have several of the antimetabolites, including methotrexate, mercaptopurine, azathioprine. 

Cells are able to synthesize genetic material (DNA, RNA) from endogenous metabolites known as purine and pyrimidine nucleotides (Fig. 36-3). Certain anticancer drugs are structurally similar to these endogenous metabolites and compete with these compounds during DNA/RNA biosynthesis. These drugs are therefore called antimetabolites because they interfere with the normal metabolites during cellular biosynthesis.16,80... 

FIGURE 36-3 Sites of anticancer antimetabolite action. Various drugs interfere with DNA/RNA production by inhibiting nucleic acid biosynthesis at specific sites indicated by the dashed lines. 

In summary, capecitabine (1), an A -carbamate pyrimidine nucleoside prodrug of cytotoxic antimetabolite 5-fluorouracil, is an FDA-approved anticancer drug that can be administered orally. This compound uses a multilayer of prodrug strategies that not only avoids side effects arising from exposure of toxic metabolites to healthy tissue but is converted to 5-fluorouracil only by enzymes preferentially expressed in many cancer cell types, thus resulting in selective delivery of the drug to tumors. Capecitabine is marketed under the trade name of Xeloda for use in the treatment of metastatic colorectal and breast cancers and metastatic breast cancer that is resistant to paclitaxel or anthracycline therapies. 

Cytamen cyanocobalamin. cytarabine [ban, inn. jan, usan] (cytarabine hydrochloride [usan] Ara C Cytosar Cytosar-U ) is an antimetabolite cytotoxic ANTICANCER and ANTIVIRAL AGENT isolated from the mushroom Xerocomm nigromaculatus. It works by interfering with pyrimidine synthesis. Clinically, it can be used sys-temically in anticancer treatment mainly of acute leukaemia, cytidine diphosphate choline dticoline. cytidine diphosphocholine dticoline. cytisine is an alkaloid with CNS STIMULANT, RESPIRATORY STIMULANT and psychoactive properties. It has been used clinically as a respiratory stimulant in Russia. It is a common cause of poisoning by the seeds of Cytisus laburnum. 

Faverin fluvoxamine. fazadinium bromide [ban. inn] is a bisquaternary amine complex heterocyclic compound, which acts as a NICOTINIC cholinoceptor ANTAGONIST, a (competitive) NEUROMUSCULAR BLOCKING AGENT. It can be used as a SKELETAL MUSCLE RELAXANT in anaesthesia, fazarabine [inn, usan] (Ara-Ac NSC 281272) is an analogue of cytarabine, an antimetabolite cytotoxic agent that has been used in ANTICANCER treatment. 

Mycil chlorphenesin tolnafitate. mycophenolate mofetil [usan] (CellCept ) is converted in vivo to n cophenolic add, which has antimetabolite cytotoxic properties. It shows experimental activity as an ANTICANCER and ANTIVIRAL AGENT. It may be clinically useful in treating psoriasis and as an ANTU.EISHMANIAL. It shows IMMUNOSUPPRESSANT properties, and is used in the prophylaxis of acute kidney rejection, mycophenolic acid [ban, inn, usan] is usually... 

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